Field of the Invention
The present invention relates to a radiation imaging apparatus, a method of controlling the same, and a radiation imaging system.
Description of the Related Art
A radiation image generated by a radiation imaging apparatus includes not only a component corresponding to incident radiation but also a component corresponding to dark charges. To remove the component corresponding to the dark charges, there is known a correction method of subtracting, from a radiation image, an image (so-called offset image) obtained in a state in which the radiation imaging apparatus is not irradiated with radiation. The generation amount of the dark charges depends on the internal temperature of the radiation imaging apparatus. Hence, if there is a difference in the temperature distribution in the radiation imaging apparatus between when an offset image is obtained and when a radiation image is obtained, the offset component may not be correctly removed. In U.S. Pat. No. 5,452,338, there is disclosed a method in which an offset image is obtained with high accuracy by updating the offset image, as needed, while radiation imaging is not being performed. Additionally, in Japanese Patent Laid-Open No. 2011-101693, there is disclosed a method that suppresses the temperature reduction of a readout IC by periodically supplying power to the readout IC even when the radiation imaging apparatus is in a sleep state.